The official TypeScript SDK for the Computer Use Protocol (CUP) — a universal protocol for AI agents to perceive and interact with any desktop UI. This package provides tree capture, action execution, semantic search, and an MCP server for AI agent integration.

Installation

# npm
npm install computeruseprotocol

# bun
bun add computeruseprotocol

Quick start

import { snapshot, snapshotRaw, overview } from "computeruseprotocol";

// Capture the foreground window's accessibility tree
const text = await snapshot();
console.log(text);

// Full accessibility tree as a CUP envelope
const envelope = await snapshotRaw();

// List all open windows (near-instant)
const windows = await overview();

Output:

# CUP 0.1.0 | windows | 2560x1440
# app: Spotify
# 63 nodes (280 before pruning)

[e0] win "Spotify" 120,40 1680x1020
  [e1] doc "Spotify" 120,40 1680x1020
    [e2] btn "Back" 132,52 32x32 [clk]
    [e3] btn "Forward" 170,52 32x32 {dis} [clk]
    [e7] nav "Main" 120,88 240x972
      [e8] lnk "Home" 132,100 216x40 {sel} [clk]
      [e9] lnk "Search" 132,148 216x40 [clk]

Session API

import { Session } from "computeruseprotocol";

const session = await Session.create();

// Capture the foreground window
const text = await session.snapshot({ scope: "foreground" });
console.log(text);

// Execute actions
await session.action("e8", "click");
await session.press("ctrl+s");
await session.openApp("notepad");

// Semantic search
const elements = await session.find({ query: "submit button" });

// Batch actions
await session.batch([
  { element_id: "e2", action: "click" },
  { action: "wait", ms: 500 },
  { action: "press", keys: "ctrl+a" },
  { element_id: "e5", action: "type", value: "hello" },
]);

CLI

# Print the foreground window's accessibility tree
npx cup

# Save full JSON envelope
npx cup --json-out tree.json

# Filter by app name
npx cup --app Discord

# Capture from Chrome via CDP
npx cup --platform web --cdp-port 9222

# Include diagnostics (timing, role distribution, sizes)
npx cup --verbose

Platform support

| Platform | Adapter | Tree Capture | Actions | |----------|---------|-------------|---------| | Windows | UIA via PowerShell + C# | Stable | Stable | | macOS | AXUIElement via Swift + JXA | Stable | Stable | | Linux | AT-SPI2 via gdbus + xdotool | Stable | Stable | | Web | Chrome DevTools Protocol | Stable | Stable | | Android | | Planned | Planned | | iOS | | Planned | Planned |

CUP auto-detects your platform. The Web adapter uses Chrome DevTools Protocol (CDP) and works on any OS. Native adapters use platform accessibility APIs via compiled helpers (C# on Windows, Swift on macOS, gdbus on Linux).

Architecture

src/
├── index.ts                    # Public API: Session, snapshot, snapshotRaw, overview
├── types.ts                    # CUP type definitions
├── cli.ts                      # CLI entry point
├── base.ts                     # Abstract PlatformAdapter interface
├── router.ts                   # Platform detection & adapter dispatch
├── format.ts                   # Envelope builder, compact serializer, tree pruning
├── search.ts                   # Semantic element search with fuzzy matching
├── actions/                    # Action execution layer
│   ├── executor.ts             # ActionExecutor orchestrator
│   ├── keys.ts                 # Key combo parsing
│   ├── web.ts                  # Chrome CDP actions
│   ├── windows.ts              # Windows UIA + SendInput actions
│   ├── macos.ts                # macOS AX + CGEvent actions
│   └── linux.ts                # Linux AT-SPI2 + xdotool actions
├── platforms/                  # Platform-specific tree capture
│   ├── web.ts                  # Chrome CDP adapter
│   ├── windows.ts              # Windows UIA adapter
│   ├── macos.ts                # macOS AXUIElement adapter
│   └── linux.ts                # Linux AT-SPI2 adapter
└── mcp/                        # MCP server integration
    ├── server.ts               # MCP protocol server
    └── cli.ts                  # Stdio transport entry point

Adding a new platform means implementing PlatformAdapter — see src/base.ts for the interface.

MCP Server

CUP ships an MCP server for integration with AI agents (Claude, Copilot, etc.).

# Run directly
npx cup-mcp

# Or with bun
bun run src/mcp/cli.ts

Add to your MCP client config (e.g., .mcp.json for Claude Code):

{
    "mcpServers": {
        "cup": {
            "command": "npx",
            "args": ["cup-mcp"]
        }
    }
}

Tools: snapshot, snapshot_app, overview, snapshot_desktop, find, action, open_app, screenshot

Contributing

CUP is in early development (v0.1.0). Contributions welcome — especially:

• Android adapter (src/platforms/android.ts)
• iOS adapter (src/platforms/ios.ts)
• Tests — especially cross-platform integration tests
• Documentation and examples

For protocol or schema changes, please contribute to computer-use-protocol.

See CONTRIBUTING.md for setup instructions and guidelines.

Documentation

• API Reference — Session API, actions, envelope format, MCP server
• Protocol Specification — Schema, roles, states, actions, compact format

License

MIT